The Minister of Agriculture, Environment and Rural Development, Francisco Martinez Arroyo stated that the regional government, through the Regional Institute for Food and Agriculture Research (IRIAF) had donated 1,600 kilos of pistachios for a study on the prevention of gestational diabetes, whose conclusions have just been published in the prestigious magazine Plos One.

The IRIAF, dependent on the Ministry of Agriculture, participated in the financial support of the research by contributing this amount of roasted pistachios without salt from the experimental cultivation fields of the Environmental Research Center of El Chaparrillo (Ciudad Real). This center "is a reference of the first order in the matter, and thanks largely to its disseminating work, the cultivation of pistachio is expanding rapidly in the center and south of the Iberian Peninsula," stated the Minister of Agriculture.

Martinez Arroyo stressed that Castilla-La Mancha concentrated more than 65 percent of the national production of this crop and that, thanks to this model promoted by the Ministry of Agriculture, there were more funds for agricultural research and the efforts made focused more on the sector's innovation requirements.

In this sense, the Mediterranean Diet Foundation that he chairs, within the nuts section, stated that pistachios were very beneficial. Healthy eating, particularly when it is rich in mono and polyunsaturated fat during pregnancy, induces epigenetic changes that are expected will give health benefits to those born after being in this intrauterine environment, and that eat this product their postnatal stage, during their pubertal development, and in their adulthood.

Obstetric researchers

The study was carried out at the San Carlos Clinical Hospital and was led by the Endocrinology and Nutrition Service. It involved researchers from the obstetrics service, the Preventive Medicine Service, and the Clinical Analysis Laboratory.

All the pregnant women who attended their first gestational visit, prior to the 12th week of gestation and that had strictly normal blood glucose levels, were invited to participate in the study. The hypothesis was that a good diet based on the Mediterranean diet, from the beginning of the pregnancy could reduce the occurrence of gestational diabetes (diagnosed with the less strict IADPSG criteria, and adopted by the World Health Organisation) between weeks 24-28 of pregnancy, as wall as a reduction of all the adverse events that may affect pregnancy, childbirth, and the health of the mother and the newborn.

The study divided 1,000 healthy pregnant women in 2 groups of 500. The control group received the usual nutritional treatment based on the Mediterranean diet, but limiting the consumption of olive oil to less than 4 tablespoons per day and that of nuts to less than 2 times a week. Meanwhile the other group was recommended to consume more than 4 tablespoons of extra virgin olive oil and pistachios on a daily basis. To achieve this, they were given 10 litres of extra virgin olive oil and 2 kg of pistachios for free in weeks 12 and 24-28 of pregnancy, to ensure that they had enough extra virgin olive oil to use daily in the preparation of all their foods and enough pistachios to consume at least 25 grams daily.

The rest of the dietary and physical exercise recommendations were identical for both groups of women. Similarly, the follow-up and number of visits were also the same. The research showed that a Mediterranean diet reduced the onset of gestational diabetes by 30 percent, and the need for insulin treatment was halved. Other benefits were also obtained, such as a significant reduction in prematurity rates, emergency caesarean sections, urinary tract infections and perineal trauma in the mother, as well as small and large newborns for gestational age. In other words, the greater adherence to the Mediterranean diet is associated with a pregnancy with fewer adverse events. In addition, they did not gain more weight during pregnancy.

The results show that both nuts, especially pistachio, and extra virgin olive oil have demonstrated favorable metabolic, anti-inflammatory, immune or antithrombotic effects. What the subjects ate was as important as where they ate. Women who have extra virgin olive oil and use it as their sole source of fat for cooking, consume more homemade foods and less commercial fried foods, as well as more vegetables and salads, that is, foods with lower caloric density. The women who had pistachios for their daily consumption ate less commercial snacks or other snacks rich in trans fats. Pistachios also offer another advantage. It takes people more time to consume the roasted and peeled pistachio presentations, which were used in this study, than other dried fruit, which increases the cephalic phase of food intake inducing early satiety. This might be the reason that this group of women didn't gain more weight.

Consumption of olive oil and pistachios is usually limited due to their high caloric content so as to better control weight gain. However, the data of the study demonstrate the opposite. When the consumption of extra virgin olive oil is liberalized, pregnant women consume a reasonable amount, rarely exceeding 5 tablespoons per day. However, they substantially reduce commercial sauces, and consume more vegetables and salads. In addition, the consumption of nuts, and in particular of pistachios - like in the study- replace other snacks and snacks with trans fat and with less capacity to satiate, so their consumption is very favorable for health as people don't eat that much. Therefore, weight gain during pregnancy is probably better controlled when the women eat both foods freely.

In summary, the nutritional recommendation during pregnancy should not limit the consumption of extra virgin olive oil and pistachios, but it should promote it. Pregnant women will rarely consume these products in excessive amounts, they induce very healthy changes in their diet, and significantly reduce the adverse events that may arise during pregnancy, delivery and in the newborn. In fact, their benefits can transcend the postnatal stage.

This study was carried out by groups of the Health Research Institute of the San Carlos Clinical Hospital (IdISSC), the Biomedical Research Center in Diabetes and Associated Metabolic Diseases Network (CIBERDEM), and it was funded by the Carlos III Institute (PI14 / 01563) and the Ministry of Agriculture of Castilla La Mancha. It can be downloaded for free at Plos One doi 10.1371 / journal.pone.0185873.